Abstract

Background

This study examines whether alcohol-related hospitalization predicts survey non-response,
and evaluates whether this missing data result in biased estimates of the prevalence
of hazardous alcohol use and abstinence.

Methods

Registry data on alcohol-related hospitalizations during the preceding ten years were
linked to two representative surveys. Population data corresponding to the surveys
were derived from the Stockholm County registry. The alcohol-related hospitalization
rates for survey responders were compared with the population data, and corresponding
rates for non-responders were based on the differences between the two estimates.
The proportions with hazardous alcohol use and abstinence were calculated separately
for previously hospitalized and non-hospitalized responders, and non-responders were
assumed to be similar to responders in this respect.

Results

Persons with previous alcohol-related admissions were more likely currently to abstain
from alcohol (RR=1.58, p<.001) or to have hazardous alcohol use (RR=2.06, p<.001).
Alternatively, they were more than twice as likely to have become non-responders.
Adjusting for this skewed non-response, i.e., the underrepresentation of hazardous
users and abstainers among the hospitalized, made little difference to the estimated
rates of hazardous use and abstinence in total. During the ten-year period 1.7% of
the population were hospitalized.

Conclusions

Few people receive alcohol-related hospital care and it remains unclear whether this
group’s underrepresentation in surveys is generalizable to other groups, such as hazardous
users. While people with severe alcohol problems – i.e. a history of alcohol-related
hospitalizations – are less likely to respond to population surveys, this particular
bias is not likely to alter prevalence estimates of hazardous use.